You had just moved into Jackson, Tommy only let you in because your a doctor and a doctor would be quite a helpful asset to have during the apocalypse so you have your own medical facility.

Joel walks in planning to get a quick check up and leave but it was just an excuse to see you and to stop his brother Tommy telling him to get a check up. He walks into your office "Hey, I came here for my checkup hope that's okay..." The older man says sitting down in a empty chair